Louis john crossley and walter emmott



(No Model.)

L. J. CROSSLEY, W. EMMOTT 85 J. F. HARRISON.

ELECTRIC SIGNALING APPARATUS.

Patented Jan. 29, 1884.

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, bell apparatus, and to or in connection with is generally used in. the magneto-calls or callbell'apparatus now in-use; but any other suitinto effect when used for UNITED STATES PATENT OFFICE?! LOUIS JOIIN .CROSSLEY AND XVALTER EMMOTT, OF HALIFAX, AND JOHN 4 FREDERIO HARRISON, OF BRADFORD, COUNTY OF YORK, ENGLAND.

ELECTRIC SIGNALING APPARATUS.

SPECIFICATION forming part of Letters 1? Application filed November 6,1882. (No model.) Patented in England April 27, 1882 No. 1 328 No. 151,128,- in Italy September 30, 1882, XVI, 14,664, XXIX,

atent No. 292,542, dated January 29, 1884,

, in France September 16,1882 192; in Belgium October 9, 1882, No. 59,224; in Victoria Novemlzcr 29, 1882,-N0. 3,356; in New South Wales January 1!), 1833,11'0. 1,183,- in Spain April 11. 1853, No. 3,748, and in Austria- ]Iuugary April 23, 1883, No. 725 and No. 15,120.

Jo aZZ whom it may concern: I

Be it known that we, LoUIs JOHN Gaoss LEY and WALTER EMMOTT, of Halifax, and J OHN FREDERIC HARRISON, of Bradford, all in the county of York, England, subjects of the Queen of Great Britain, have invented certain new and useful Improvements in Electric Signaling Apparatus, applicable also toother purposes, (for which we have obtained a patent in Great Britain, No. 1,328, bearing dateMarch 18, 1882, and sealed April 27, 1882,) of which the following is a specification.

This invention relates to improvements in magneto-electric or electromagnetic signaling apparatus for use in telephone-exchanges, railway-signal cabins, and for telegraphic and telephonic purposes generally, the improved signaling apparatus being also applicable to connecting and disconnecting wires used for telephonic, telegraphic, and other purposes.

For the purpose of illustration we will de scribe our invention as applied for use in tele phone-exchanges. 1

We take an ordinary magneto electric callthe axis or spindle of the revolving coil or coils we adapt one or more cams, pins, or the like, so that it or they will make contact with a suitably-placed spring or springs or its or their equivalent in such a manner that when the said coil or coils is or are rotated the electric currents are caused to flow out to the line in the direction or directions required by operating a key or by other suitable means. By this arrangement the subscribers to a telephone-exchange, in addition to the ordinary call-signal, are enabled to transmit a distinct and separate signal to advise the exchange-operator that the wires are free. g

In order to enable our'invention to be better understood, we will proceed to describe a suitable arrangement for carrying the same telephone-exchanges, by reference to the accompanying drawings, in which- 7 Figure 1 represents a view of a coil such as able form of coil may be employed in carrying out our improvements. Fig. 2 represents .3 represents a view showing a suitable arthe figures represent 6 -l0ws: A casting is made (shown in Figs. 1 and 2) in the recess A, running the length of the casting, and shown-in Fig; 2,a quantityof 6 wire is wound, the two ends of which are connected to I? and P, respectively. The armature thus formed is inclosed in an iron frame, which forms the poles of a compound magnet, and between which the armature is free to rotate. It is well known that on rotating a bobbin of wire of this nature between the poles of amagnet induced currents of electricity are produced in the wire, and these currents are alternately positive and negative, and as 7 5 such are used for ringing magnet-bells .for telephonic signaling and other purposes. I Suppose it is desired to transmit signals to advise the operator in a telephone-exchange, sothat the wires which he has put through may be disconnected. This can only be done by arranging a code of signals, using a certain number of rings for one expression and a certain number for another expression; This has, however, been found to be impracticable, s 5

as the subscribers are very liable to make mistakes, while the operators are very liable to miss the signal, in consequence of their attention being otherwiseengaged at the moment the signal is transmitted. It isto remedy these defects that we brought out ourin proved apparatus, and after most carefubtigials, it

proved to meet every demand. .7 -.1 i i y In order to enable the subscribers to transmit a special signal when they/have finished withtheir connection, and to save the annoyance caused by lines being left through too long, we arrange the bell in such a manner that the same bell serves to transmit the separate and distinct signal, which can be made to record itself either visually or audibly., This is accomplished by attaching to the spindle of the bobbin a cam, pin, or other projection, 0. Once in every revolution of the armature the cam 0 comes in contact with the spring J during j ust suflicient of its movement to transmit one of the two currents generatedthat is to say, either always a positive or always a negative current. For example, if the key K has been depressed by the finger and the coil rotated, it will be seen that the currents of one polarity taken off the generator will flow in the direction shown by the arrows, through the spring to the center of the key K, through the line to the exchange or elsewhere, where the indicator I is placed, and entering the indicator at terminal 1, the current passes through the coil and out cit-her to earth'in the case of a terminal station or to the next subscribers line. The indicator I, as shown in Fig. 3, is pivoted a 1/, and to it is attached, as shown, the magnet M, which is provided with'the forks H H. 1f the key were not depressed, it will be seen, by following out the connections, that the currents are taken off direct from the contactpin I, through the spring. J, to the repose-contact, and thence, through the key, out to the line, as shown by the arrows. From this it will be seen that all the currents generated in the revolving armature will be taken off through this circuit, in contradistinction to the case when the key is pressed and only the currents taken off from the cam C, making contact wit-h the spring J once in each revolution, thus taking off a current in one direction only. \Vhen the key is not pressed, all the currents generated in the armature pass out through the insulated pin through the spring to the key and out to line. \Vhile,when the key is pressed, the cam comes into circuit at each revolution, and sendsonly the currents generated as it makes contact with the spring, the spring being only connected to line when the key is pressed. \Vhen the key is pressed, the circuit through the spring J is broken by the separation of the plates at (See Fig. 2.)

Suspended over the coil in the indicator' is a light curved magnet, M, and when no current passes this magnet remains bythe force of gravity in the position shown over a coil or coils of wire, B; but immediately a current of electricity of one polarity flows through the indicator the needle H is deflected, as shown in dotted lines, to the right or to the left in accordance with the direction of the current viz., either positive or negative. Immediately the magnet is deflected to either of these positions, the fork H, at the end of the curved magnet, comes into contact with the mercury in' the mercury-cup O, and this closes a local circuit, which may contain a bell, relay, drop-indicator, or any other appliance to attract attention; but a bell is shown in the drawings.

' From this description it will be gathered that the rapidly-aiternating currents transmitted when the key K is not pressed do not deflect the curved ma gnet-indicatorsirffi ciently to either side to make contact with the mercury-cups; and it will also be seen from this that one subscriber to an exchange can call up his fellow subscriber, to whom he has been put through as often as he may desire without the operator in central exchange knowing anything about it; but the moment either subscriber presses his ring-off key the indicator falls over, short-circuits the two mercury cups, and rings the bell or otherwise advises the operator, who should at once put the lines straight again, ready for the next call.

If the curved magnet M be weighted slightly on one side, it may be used without a local circuit and additional apparatus, as the indicator I will fall over when deflected and remain until put back.

, Fig. 3 is a detail view,showing the mercury cups in section and the fork.

There are numerous other useful application of this system. For instance, an intermediate station can be arranged with two terminal stations, so that the terminals can speak with each other or with the intermediate station, the switching being done by the station wishing to speak, as will be well understood without further description. The system is also applicable to the working of electric signals on railways instead of using batteries, as at p resent. For example,the ringoff key or other suitable arrangement will enable the operator to transmit the currents, so as to indicate line clear and line blocked, or otherwise, as required.

It will be seen by referring to the indicator with the curved magnet that the local circuit, instead of including the two bells shown, may have an ordinary single needle-block dial, which will indicate line clear or line blocked, according to the side to which the curved magnet is deflected, such direction being governed by the direction of the current.

Having thus described our invention and a suitable manner of carrying the same into effect, we wish it to be understood that what we claim is-'- The combination, in a telephonicexchange syste1n,with the axis or spindle of the revolving coil or coils of a magneto-electric callbell apparatus, of one or more cams, pins, or the like, key 1C, and its springs J and J, whereby, in addition to the ordinary call-signal,a distinct and separate signal may be transmitted to advise the exchange-operator that the wires are free, substantially as hereinbefore described.

LOUIS JOHN GROSSLEY. \VALTER EMMOTT. JOHN FREDERIO HARRISON.

Witnesses to the signatures of Louis John Grossley and Walter Emmott:

\VALTER J as. TURxnR, Ton lrr'rs.

YVitnesses to the signature of John Frederic Harrison \VALTER J AS. TURNER, SAMUEL A. DRACUP. 

